Outcomes associated with planned place of birth among low-risk pregnancies in Ontario, Canada (2012-2021): A protocol for a population-based propensity score weighted cohort study

PLoS One. 2024 May 13;19(5):e0302489. doi: 10.1371/journal.pone.0302489. eCollection 2024.

Abstract

Background: Evidence suggests that for low-risk pregnancies, planned home births attended by a skilled health professional in settings where such services are well integrated are associated with lower risk of intrapartum interventions and no increase in adverse health outcomes. Monitoring and updating evidence on the safety of planned home births is necessary to inform ongoing clinical and policy decisions.

Methods: This protocol describes a population-based retrospective cohort study which aims to compare risk of (a) neonatal morbidity and mortality, and (b) maternal outcomes and birth interventions, between people at low obstetrical risk with a planned home birth with a midwife, a planned a hospital birth with a midwife, or a planned hospital birth with a physician. The study population will include Ontario residents who gave birth in Ontario, Canada between April 1, 2012, and March 31, 2021. We will use data collected prospectively in a provincial perinatal data registry. The primary outcome will be severe neonatal morbidity or mortality, a composite binary outcome that includes one or more of the following conditions: stillbirth during the intrapartum period, neonatal death (death of a liveborn infant in the first 28 completed days of life), five-minute Apgar score <4, or infant resuscitation requiring cardiac compressions. We will conduct a stratified analysis with three strata: nulliparous, parous-no previous caesarean birth, and parous-prior caesarean birth. To reduce the impact of selection bias in estimating the effect of planned place of birth on neonatal and maternal outcomes, we will use propensity score (PS) overlap weighting (OW) and modified Poisson regression to conduct multivariate analyses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Apgar Score
  • Cohort Studies
  • Delivery, Obstetric / statistics & numerical data
  • Female
  • Home Childbirth / statistics & numerical data
  • Humans
  • Infant
  • Infant Mortality
  • Infant, Newborn
  • Ontario / epidemiology
  • Pregnancy
  • Pregnancy Outcome / epidemiology
  • Propensity Score*
  • Retrospective Studies

Grants and funding

EKD and AR received funding (one single award). The grant does not have a number. The funder is the Association of Ontario Midwives. URL: https://www.ontariomidwives.ca/research-grants The funder did not play any role in the study design for this protocol, data collection and analysis, the decision to publish, or preparation of the manuscript.